Set Content-Type header in do_parse_request filter

Question

I have a plugin that sends binary content inside a do_parse_request filter and I need to set the proper Content-Type header but when I do it I got an error saying that Headers was already sent.

How can I prevent wordpress from sending headers until my plugin have done it's work?

Answer 1

Call the do_parse_request in the plugins_loaded action hook.

add_action('plugins_loaded', setup_parse_request' );

function setup_parse_request() {
    // handle parse request
}